Most Helpful Guy

Imagine yourself as a person, as a blank canvas.You might have a thing for artistic expression and that then correlates to blue paint on the canvas, then you might be into videogames and that's the red paint. and so on. Your attributes, your personality and your interest is basically the same as the paint in this scenario.

"girl" is used in the sense of a template, a blank slate, and then the attributes are put into those templates. What he means with "you're everything I look for in a girl" is that you have all of the attributes he likes, that you're a completed painting. What he views as a piece of art.